Recent discussion about pasture persistence concentrates on pastures based on perennial ryegrass, the most commonly used grass species. This paper raises the question as to whether some of the causes of poor pasture persistence are due to perennial ryegrass being used in environments to which it is not suited. The adaptation to environmental stresses, particularly water, temperature and nutrien...

Some effects of l&m endophyte (Acremonium lolioe) on sheep production were evaluated using pure swards of h igh (SO%>) and low (< 5%) endophyte Nui and Ar ik i ryegrass. The proportion of infected t i l lers in high endophyte treatments increased by 19% in 15 months. Ryegrass staggers occurred on both high endophyte ryegrasses being sl ight ly worse on Nui . The peak ryegrass staggers outbreak ...

Four weed species (Bromus mollis, Vulpia sp., Poa annua, Steltaria media) occur in 30% or more of all perennial ryegrass seed samples. Of the listed undesirable species, Avena fatua (wild oat) and Hordeum murinum occurred respectively in 5.3 and 3.5% of ryegrass seedlots. Only 6 herbicides are registered for use in grass seed crops in New Zealand, 2 for wild oat, and 4 for broadleaved weeds. Th...

Asexual Epichloë endophytes colonize agricultural forage grasses in a relationship which is mutually beneficial and provides the host plant with protection against herbivorous insects. The endophyte strain AR37 (Epichloë festucae var. lolii) produces epoxy-janthitrem alkaloids and is the only endophyte known to provide ryegrass with resistance against porina larvae (Wiseana cervinata (Walker)),...

Perennial ryegrass (Lolium perenne) is the most widely grown temperate grass species globally. Intensive plant breeding in ryegrass compared to many other crops species is a relatively recent exercise (last 100 years) and provides an interesting experimental system to trace the extent, impact and trajectory of undomesticated ecotypic variation represented in modern ryegrass cultivars. To explor...

Understanding the stability of chloropyromorphite (CPY) is of considerable benefit for improving risk assessment and remediation strategies in contaminated water and soil. The stability of CPY in the rhizosphere of phosphorus-deficient ryegrass was evaluated to elucidate the role of root-secreted low molecular weight organic acids (LMWOAs) on the dissolution of CPY. Results showed that CPY trea...

An experiment investigated whether the inclusion of chicory (Cichorium intybus) in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne). Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Bluecross steers were used in the first gra...

A bar-slider framework is a bar-joint framework a part of whose joints are constrained by using line-sliders. Such joints are allowed to move only along the sliders. Streinu and Theran proposed a combinatorial characterization of the infinitesimal rigidity of generic bar-slider frameworks in two dimensional space. In this paper we propose a generalization of their result. In particular, we prov...

There is uncertainty about the potential reduction of soil nitrous oxide (N(2)O) emission when fertilizer nitrogen (FN) is partially or completely replaced by biological N fixation (BNF) in temperate grassland. The objectives of this study were to 1) investigate the changes in N(2)O emissions when BNF is used to replace FN in permanent grassland, and 2) evaluate the applicability of the process...

Cinnamoyl CoA-reductase (CCR) and caffeic acid O-methyltransferase (COMT) catalyze key steps in the biosynthesis of monolignols, which serve as building blocks in the formation of plant lignin. We identified candidate genes encoding these two enzymes in perennial ryegrass (Lolium perenne) and show that the spatio-temporal expression patterns of these genes in planta correlate well with the deve...